Naive Time-reversal Odd Phenomena in Semi-inclusive Deep-inelastic Scattering from Light-cone Constituent Quark Models

Naive Time-reversal Odd Phenomena in Semi-inclusive Deep-inelastic Scattering from Light-cone Constituent Quark Models PDF Author:
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Languages : en
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We present results for leading-twist azimuthal asymmetries in semi-inclusive lepton-nucleon deep-inelastic scattering due to naively time-reversal odd transverse-momentum dependent parton distribution functions from the light-cone constituent quark model. We carefully discuss the range of applicability of the model, especially with regard to positivity constraints and evolution effects. We find good agreement with available experimental data from COMPASS and HERMES, and present predictions to be tested in forthcoming experiments at Jefferson Lab.

Naive Time-reversal Odd Phenomena in Semi-inclusive Deep-inelastic Scattering from Light-cone Constituent Quark Models

Naive Time-reversal Odd Phenomena in Semi-inclusive Deep-inelastic Scattering from Light-cone Constituent Quark Models PDF Author:
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Languages : en
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Book Description
We present results for leading-twist azimuthal asymmetries in semi-inclusive lepton-nucleon deep-inelastic scattering due to naively time-reversal odd transverse-momentum dependent parton distribution functions from the light-cone constituent quark model. We carefully discuss the range of applicability of the model, especially with regard to positivity constraints and evolution effects. We find good agreement with available experimental data from COMPASS and HERMES, and present predictions to be tested in forthcoming experiments at Jefferson Lab.

Phases of Augmented Hadronic Light-Front Wave Functions

Phases of Augmented Hadronic Light-Front Wave Functions PDF Author:
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Languages : en
Pages : 10

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It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators.

Deep Inelastic Scattering and Light-cone Wave Functions

Deep Inelastic Scattering and Light-cone Wave Functions PDF Author:
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Languages : en
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In the framework of light-cone QCD rules, we study the valence quark distribution function [ital q]([ital x][sub B]) of a pion for moderate [ital x][sub B]. The sum rule with the leading twist-2 wave function gives [ital q]([ital x][sub B]) = [phi][sub [pi]]([ital x][sub B]). Twist-4 wave functions give about 30% for [ital x][sub B] [approx]0.5. It is shown that QCD sum rule predictions, with the asymptotic pion wave function, are in good agreement with experimental data. We found that a two-hump profile for the twist-2 wave function leads to a valence quark distribution function that contradicts experimental data.

Deep Inelastic Scattering

Deep Inelastic Scattering PDF Author: Jerome I. Friedman
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Category :
Languages : en
Pages : 22

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Light Cone Expansions and Deep Inelastic Electron and Neutrino Scattering

Light Cone Expansions and Deep Inelastic Electron and Neutrino Scattering PDF Author: Michael Anthony Keppel-Jones
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Category : Electrons
Languages : en
Pages : 160

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Single Transverse-Spin Asymmetries at Large-x

Single Transverse-Spin Asymmetries at Large-x PDF Author:
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Category :
Languages : en
Pages : 20

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The large-x behavior of the transverse-momentum dependent quark distributions is analyzed in the factorization-inspired perturbative QCD framework, particularly for the naive time-reversal-odd quark Sivers function which is responsible for the single transverse-spin asymmetries in various semi-inclusive hard processes. By examining the dominant hard gluon exchange Feynman diagrams, and using the resulting power counting rule, we find that the Sivers function has power behavior (1-x)4 at x --> 1, which is one power of (1-x) suppressed relative to the unpolarized quark distribution. These power-counting results provide important guidelines for the parameterization of quark distributions and quark-gluon correlations.

Coherence Effects in Deep Inelastic Scattering from Nuclei

Coherence Effects in Deep Inelastic Scattering from Nuclei PDF Author:
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Category :
Languages : en
Pages : 5

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A complete theoretical picture of multiple scattering processes in QCD remains elusive. In deep inelastic scattering experiments (DIS), we hope to find out information about the internal structure of nuclei from inelastically scattering high-energy electrons off them. The electrons interact via virtual photon exchange with the target. In the target rest frame the virtual photon splits into a quark-antiquark pair which is then scattered off the target color field. At high energies, coherent multiple scattering within the nucleus takes place. We develop a model that uses a parameterization of scattering cross section of the quark-antiquark pair off the proton to predict the cross section suppression known as shadowing in larger nuclei. This model takes the possibility of multiple scattering into account using Glauber high-energy collision theory. In large nuclei we must also move beyond the eikonal approximation by correcting for the finite lifetime of the quark-antiquark pair inside the nucleus. Results and implications of this model in relation to available data will be discussed. Finally, application of this type of model to predicting gluon densities will be considered. Understanding this process can give us insights into the more oomplicated scattering taking place in heavy ion colliders such as RHIC and LHC.

Transverse Spin Effects in Polarized Semi-inclusive Deep Inelastic Scattering

Transverse Spin Effects in Polarized Semi-inclusive Deep Inelastic Scattering PDF Author: Luciano L. Pappalardo
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ISBN:
Category :
Languages : en
Pages : 235

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QCD-instanton Induced Final States in Deep Inelastic Scattering

QCD-instanton Induced Final States in Deep Inelastic Scattering PDF Author:
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ISBN:
Category :
Languages : en
Pages : 5

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Deep Inelastic Scattering and QCD

Deep Inelastic Scattering and QCD PDF Author: J. Blumlein
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Category :
Languages : en
Pages :

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